Interest Groups are different than regular groups, since the constituent determines where their interests lie. To edit a constituent's membership of an Interest Group, their interest selections must be changed in Luminate Online. 
  1. Navigate to Constituent360 > Constituents
  2. Enter the name of the constituent
  3. Click Find
  4. Click Edit under the Actions column
  5. Select the Email Preferences tab
  6. Click the 'Edit Site-Wide Preferences' button
  7. Find the Email Interest Group in question and select the appropriate Status from the drop-down menu
  8. Click Save